diff --git a/services/baremetal-builder/default.nix b/services/baremetal-builder/default.nix
index b780d31..de06765 100644
--- a/services/baremetal-builder/default.nix
+++ b/services/baremetal-builder/default.nix
@@ -149,6 +149,7 @@ in
       description = "Nix Garbage Collector";
       script = "exec ${config.nix.package.out}/bin/nix-store --gc --store /mnt";
       serviceConfig.Type = "oneshot";
+      serviceConfig.User = "builder";
       startAt = "hourly";
     };
     systemd.timers.hydra-gc.timerConfig.Persistent = true;